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Multiscale Modeling of a Germanium Quantum Dot in Silicon

  • V. K. Tewary
  • D. T. Read
Conference paper

Abstract

A method is described for multiscale modeling of a quantum dot in a semiconductor solid containing a free surface. The method is based upon the use of lattice-statics and continuum Green’s functions integrated with classical molecular dynamics. It fully accounts for the nonlinear discrete lattice effects inside and close to the quantum dot, discrete lattice structure of the host solid near the quantum dot and reduces asymptotically to the macroscopic continuum model near the free surface. Our method can model a large crystallite containing, for example, a million atoms without excessive CPU effort and it connects nanoscales seamlessly to macroscales. The method relates the physical processes such as lattice distortion at the atomistic level to measurable macroscopic parameters such as strains at a free surface in the solid. The method is applied to calculate the lattice distortion around a Ge quantum dot in Si. Preliminary numerical results are reported.

Key words

germanium in silicon lattice Green’s functions molecular dynamics multiscale modeling quantum dots 

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Copyright information

© Springer 2006

Authors and Affiliations

  • V. K. Tewary
    • 1
  • D. T. Read
    • 1
  1. 1.National Institute of Standards and TechnologyBoulderUSA

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